https://www.sciencedaily.com/releases/2019/01/190129124814.htm

A new study by researchers from the University of Illinois at Urbana-Champaign and Georgia Tech compared and analyzed county data from 2001 and 2009. They found that a single percentage-point increase in mass transit ridership is associated with a 0.473 percentage-point lower obesity rate in counties across the United States.

"Opting for mass transit over driving creates opportunities for exercise that may otherwise not exist," said?Sheldon H. Jacobson, a co-author of the study and a Founder Professor of Computer Science at Illinois. "Instead of just stepping out of the house and into his car, riders need to walk from their home to a bus stop and from their stop to their destination."